The invention relates to the field of penetrators. More specifically, the invention relates to a strengthened penetrator, wherein the strengthened penetrator employs specific materials in a set configuration.
Numerous types of penetrators exist. Tungsten is often a material of choice in the penetrator art. A typical method for fabricating penetrators from tungsten involves the use of tungsten powder metal, which is a heterogeneous mixture of tungsten and other metal powders. The mixture of powders is compacted into the desirable shape, liquid phase sintered and processed into penetrators.
Additional materials commonly employed in the penetrator art are depleted uranium and liquid phase sintered tungsten metals and alloy variations thereof. The use of uranium in penetrators is undesirable due to its radioactive properties. The need exists to study the properties of various compounds while, at the same time, taking into consideration the requirements or standards of those interested in producing a penetrator having enhanced strength and penetration ability. Materials of choice would be those that would optimize the desired properties of penetrators.
Prior art projectiles, such as those taught in Statutory Invention Registration H343, have been modified by employing composite fiber reinforcement materials therein. These fiber reinforcement materials have been woven throughout the make up of a penetrator to enhance the strength and penetrating ability of the resulting product. In this reference, the fibers employed are wires such as those composed of tungsten-hafnium-carbide (column 3, lines 32+) and tungsten generally (column 3, lines 61+).
U.S. Pat. No. 4,961,383, issued to Fishman et al., teaches a composite tungsten-steel armor penetrator. The penetrator taught therein comprises an iron or steel matrix which is reinforced with heavy metal wires or rods. These wires or rods may be composed of tungsten, among numerous other materials taught.
The use of heavy metal wires as a reinforcing means in the penetrator art is equally taught in Jackson, U.S. Pat. No. 4,841,868. Jackson teaches a composite long rod penetrator composed primarily of depleted uranium and titanium. This penetrator may be reinforced with tungsten wire filaments.
Single crystal bodies are taught as having strengths which are relatively greater than polycrystalline bodies. Note, U.S. Pat. No. 4,867,061, issued to Sadler et al. More specifically, Sadler et al. teaches the employ of tungsten or an alloy of tungsten into penetrator constructions. Reference is made to the [100] crystal orientation of tungsten--note column 3, lines 49+.
The criticality of and the effect of the type of crystal orientation employed in single crystal penetrators was addressed by Bruchey et al. in "The Effect of Crystallographic Orientation on the Performance of Single Crystal Tungsten Sub-Scale Penetrators," Interim Memorandum Report No. 941, Ballistic Research Laboratory, Aberdeen Proving Ground, Md. (April, 1990). This memorandum, beginning at the paragraph bridging pages 5 and 6 therein, teaches that the study conducted using the [100] orientation of tungsten indicated that this orientation had the best penetration performance.
In summary, the prior art generally teaches the well known use of tungsten, and more specifically tungsten having [100] orientation, in the penetrator art. The prior art additionally sets forth that metallic wires containing tungsten, in various forms, have been employed to reinforce the strength of penetrators. Moreover, it is also known in the art that single crystal bodies elicit better properties than polycrystalline bodies.
Although much research has been conducted in the penetrator art to develop a penetrator having enhanced strength and penetration ability, the invention herein sets forth a superior, single crystal, tungsten based penetrator not taught or even suggested by the above teachings.
The prior art references do attempt to develop a penetrator having enhanced properties and characteristics, however, nowhere do these references teach the use of tungsten whiskers in penetrators. Moreover, nowhere do any of the teachings even suggest the employ of whiskers, tungsten whiskers or more specifically tungsten [100] whiskers, in the penetrator art.
Applicant has discovered that the use of tungsten [100] whiskers, which must be carefully produced under controlled laboratory conditions, in penetrators creates a superior penetrator having enhanced strength and penetration ability.